• Dan Williams's avatar
    x86/NUMA: Provide a range-to-target_node lookup facility · 5d30f92e
    Dan Williams authored
    The DEV_DAX_KMEM facility is a generic mechanism to allow device-dax
    instances, fronting performance-differentiated-memory like pmem, to be
    added to the System RAM pool. The NUMA node for that hot-added memory is
    derived from the device-dax instance's 'target_node' attribute.
    
    Recall that the 'target_node' is the ACPI-PXM-to-node translation for
    memory when it comes online whereas the 'numa_node' attribute of the
    device represents the closest online cpu node.
    
    Presently useful target_node information from the ACPI SRAT is discarded
    with the expectation that "Reserved" memory will never be onlined. Now,
    DEV_DAX_KMEM violates that assumption, there is a need to retain the
    translation. Move, rather than discard, numa_memblk data to a secondary
    array that memory_add_physaddr_to_target_node() may consider at a later
    point in time.
    
    Cc: Dave Hansen <dave.hansen@linux.intel.com>
    Cc: Andy Lutomirski <luto@kernel.org>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Cc: Borislav Petkov <bp@alien8.de>
    Cc: "H. Peter Anvin" <hpa@zytor.com>
    Cc: <x86@kernel.org>
    Cc: Andrew Morton <akpm@linux-foundation.org>
    Cc: David Hildenbrand <david@redhat.com>
    Cc: Michal Hocko <mhocko@suse.com>
    Reported-by: default avatarkbuild test robot <lkp@intel.com>
    Reviewed-by: default avatarIngo Molnar <mingo@kernel.org>
    Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
    Reviewed-by: default avatarThomas Gleixner <tglx@linutronix.de>
    Link: https://lore.kernel.org/r/158188326978.894464.217282995221175417.stgit@dwillia2-desk3.amr.corp.intel.com
    5d30f92e
numa.c 23.6 KB